溶胶-凝胶法制备二氧化钛纳米粒子及在光固化体系中的稳定分散

选用3种不同的稳定剂,乙酰丙酮(acac),异丙氧基三(焦磷酸二辛酯)钛(TTPO)和可聚合有机磷酸酯(MAP),采用钛酸四正丁酯(TBT)通过溶胶-凝胶法合成了一系列二氧化钛溶胶,并与树脂/单体相混合,制备成有机-无机杂化光固化涂料.利用FT-IR监测了TBT水解缩合形成溶胶的过程及杂化体系的光聚合过程.杂化固化膜SEM结果显示,在合成溶胶过程中添加不同的稳定剂对杂化固化膜中无机粒子粒径尺寸等形态有显著影响,其中使用TTPO作为稳定剂得到的无机粒子分散最均匀,粒径最小,约20 nm.物理性能测试表明光固化杂化膜在硬度和柔韧性方面都有明显的改善.

STABILIZED DISPERSION OF TITANIA NANOPARTICLE IN UV-CURABLE MATRIX THROUGH SOL-GEL PROCESS

Organic-inorganic hybrid UV-curable coatings were synthesized through blending the UV-curable components and the stabilized titania sol prepared via sol-gel process of tetrabutyl titanate(TBT) with three different stabilizers,acetoacetone(acac),isopropyl(tri(dioctyl)pyrophosphato) titanate coupling agent(TTPO) and a polymerizable organic phosphoric acid(MAP).FT-IR was employed to follow the sol process and the photopolymerization of the hybrid systems.The SEM observation of etched photocured hybrid film showed that the size and dispersion of titania particle in the organic matrix were dominated by the properties of these stabilizers.The inorganic particles in the hybrid cured film uniformly dispersed with the diameter of about 20 nanometers if TTPO used as stabilizer during sol-gel process.Physical properties of the hybrid cured film were determined,it is interesting that the hardness and flexibility of the photocured hybrid films were improved simultaneously contrasted to those of pure organic UV-curable formulation.